华中丘陵红壤物理性质空间变异性的研究

SPATIAL VARIABILITY OF PHYSICAL PROPERTIES OF RED SOIL IN HILLY LAND OF CENTRAL CHINA

Spatial variability of saturated hydraulic conductivity, clay and physical clay particles, water-stable aggregate and porosity of red soil were studied using a geostatistical method. Field experiments were undertaken on a red soil at Yingtan, Jiangxi Province, Clhina. There were thirty sampling locations in the experimental field with an area of 50×100 m. The autocor relation distances of various physical parameters determined in field were different according to the analysis of sermivariogram and autocorrelogram: saturated hydraulic conductivity of soil 42.0 m, clay 43.5m, physical clay 56.0 m, macroaggregate 47.0 m, total porosity 65.0m,porosity in diameter of > 0.03 mm 37.5 m and clay in layer B (20-30 cm) 45.0 m. The estimation of seven soil parameters by using Kriging interpolation method shows chat Kriging method was obviously better than Jackkniffing technology. Its estimated error was lust 67.5-30.5% of Jackniffings. Tlae saturated hydraulic conductivity of soil was esti0 mated by porosity in diameter of >0.01 mm and the clay content in B layer was estiamted by clay content in A layer in terms of Colcringing technology. Its estimated error was only 54.1-65.5% of that of linear regression method arid 36.2-86% of Kriging's respectively.